Carton



O. L. VINES Aug. 25, 1959 CARTON 2 Sheets-Sheet 1 Filed Dec. 21, 1955 INVENTOR Oscar L. Vines ATTO RNE 0. L. VINES Aug. 25, 1959 CARTON 2 Sheets-Sheet 2 Filed Dec. 21, 1955 INVENTOR Oscar L. Vines BY 75;; M, M, mg?

United States Patent CARTON Oscar L. Vines, New York, N.Y., assignor to Continental Paper Company, Ridgefield Park, NJ., a corporation of New Jersey Application December 2 1, 1955, Serial No. 554,567 7 Claims. (Cl. 229-16) This invention relates to folding cartons, and more particularly to five-sided open top carton construction having sloping side walls.

It has been proposed heretofore to package comestible articles, such as fresh fruits and berries, for distribution and sale in a five-sided or open top container or carton formed from a single rectangular piece of a suitable sheet material such as paper board. The rectangular piece of sheet material comprising the carton blank is provided with lateral fold lines that define the panels which form the two side walls and the top and bottom walls of the erected carton. The top panel is further provided with a pair of fold sections which are folded downwardly and inwardly into the carton to form the end walls thereof when the carton is erected. In order to be produced at a cost competitive with other types of open top cartons, the carton blank must be manufactured by high speed mass production methods and must be assembled and erected into the desired carton by high speed automatic machinery. As a direct consequence of the fact that the carton blank must be folded, glued and erected by the said automatic machinery, the width of the two side walls and the width of the top and bottom panels, respectively, must be substantially the same, and therefore the opposite walls of the carton are .parallel to one another. The resulting rectilinear carton makes it difficult to treat with a gaseous agent the material packaged in a group of filled cartons placed side by side. Moreover, the straight sides of the carton make the carton unsuitable as a container for certain delicate and perishable foods, and the fact that the top of the carton is the same width as the bottom has led to some difficulty in stacking one carton on top of another for shipment and display.

I have now developed a five-sided carton structure of the type described which is provided with side walls that diverge or slope outwardly slightly toward the top of the carton, thus adapting the carton for use with the aforementioned perishable fruits and berries. Moreover, the width of the bottom Wall of my new carton is appreciably less than the width of the top wall of the carton, thus facilitating stacking of the cartons for shipment and display. My new carton structure is formed from a rectangular carton blank resembling, in general, the carton blank of the aforementioned prior art cartons. However, the side and end walls of my new carton blank are so modified that when the carton is erected a portion of both side wall panels become added to the top wall panel of the carton, thus increasing the width of the top wall with respect to the bottom wall of the carton, with the resulting outward divergence of the side walls toward the top of the carton.

The carton blank from which the new carton construction of my invention is formed comprises a substantially rectangular piece of sheet material provided with a plurality of spaced parallel fold lines extending laterally across the blank, the lateral fold lines defining serially a first side panel, a top panel, a second side panel, a bot- ICC tom panel, and a glue panel. The lateral fold lines defining the lateral edges of the top panel are spaced apart the same distance as the lateral fold lines defining the lateral edges of the bottom panel. The top panel and the adjoining portions of the two side panels are formed with a pair of fold sections adapted to be folded downwardly and inwardly into the interior of the carton to form the end walls thereof, the fold sections being defined by a pair of longitudinally disposed fold lines extending across the top panel adjacent each longitudinal edge thereof, a pair of laterally disposed channel-shaped :cut lines each connecting proximate ends of the pair of longitudinal fold lines and extending an appreciable distance into the proximate side wall panels, and a longitudinal out line connecting the two channel-shaped cut lines approximately intermediate the pair of longitudinal fold lines. Each of the fold sections is wider than the top panel adjacent the longitudinal fold line connecting the fold section to the top panel, and is the same width as the bottom panel adjacent the longitudinal cut line forming the bottom edge of the fold section. Each of the side panels is provided with supplemental lateral fold lines spaced an appreciable distance from the lateral fold line defining the boundary between the said side panel and the top panel. These supplemental lateral fold lines extend from the proximate longitudinal edge of the rectangular carton blank to the proximate channel-shaped out line. The longitudinal cut line connecting the two channel-shaped cut lines between the two longitudinal fold lines is configured to define latching tongue portions along the abutting edges of the two fold sections, the latching tongue portions advantageously being provided with ear portions. The bottom panel is provided with openings adapted to receive the latching tongue portions of each fold section when the fold section is folded downwardly and inwardly into the interior of the erected carton. Each of the openings in the bottom panel is formed with tWo laterally disposed cut lines and a longitudinally disposed out line extending between the said laterally disposed cut lines.

When the carton blank of my invention is erected to form a five-sided or open-top carton, the extra width of the portions of the two fold sections adjacent the top panel causes the portion of each of the side panels disposed between the supplemental lateral fold line and the proximate lateral fold line defining the boundary between the side panel and the top panel to become added to the top panel. As a result, the top panel is appreciably wider than the bottom panel and the side walls of the carton slope or diverge outwardly toward the top of the erected carton.

The carton construction of my invention will be better understood from the following description, in conjunction with the accompanying drawings of which Fig. l is a plan view of the rectangular carton blank of my invention;

Fig. 2 is a perspective View of the partially erected carton of my invention showing the appearance of the top and side walls of the carton before and after the fold sections are folded downwardly into the interior thereof;

Fig. 3 is a fragmentary perspective View showing one end of the fully erected carton;

Fig. 4 is a fragmentary plan view of a modification of the carton blank of my invention;

Fig. 5 is a fragmentary perspective view showing one end of the carton formed from the carton blank of Fig. 4;

material such as paper board that is provided with appropriate cut lines, fold lines and glue strips as shown in Fig. 1, and that is referred to as a carton blank. The substantially rectangular carton blank is formed with a plurality of spaced parallel foldlines 11 extending laterally across the blank and defining serially a first side panel 12, a top panel 13, a second side panel 14, a bottom panel and a glue'panel 16. The top panel 13 and the adjoining portions of the two side panels 12 and 14 are formed with a pair of fold sections 17 that, when folded downwardly and inwardly into the erected carton, become the two end walls thereof, leaving the top of the carton open to view. Due to the fact that the carton blank must be folded, glued and erected by high speed automatic machinery it is necessary that the width of the first side panel 12 be the same as the width of the second side panel 14, and that the width of the top panel 13 be the same as the width of the bottom panel 15. That is to say, it is necessary that the lateral fold lines 11 defining the edges of the first side panel 12 be spaced apart the same distance as the lateral fold lines 11 defining the edges of the second side panel 14, and that the lateral fold lines 11 defining the edges of the top panel 13 be spaced apart the same distance as the lateral fold lines 14a defining the edges of the bottom panel 15. Because the two-side panels and the top and bottom panel are the same width, respectively, the side walls of the resulting carton are, of necessity, parallel to each other and are substantially normal to the top and bottom walls thereof.

It is the purpose of my invention to provide a carton having sloping side walls that diverge outwardly toward the top wall of the carton, rather than the aforesaid parallel side walls, despite the fact that the carton when initially folded is formed with top and bottom walls of equal width. To accomplish this result, the side wall panels 12 and 14 and the fold sections 17 are formed so that the portion of each side wall panel adjoining the top panel will become added to the top panel when the fold sections are folded downwardly into the erected carton.

As heretofore pointed out, the top panel 13 and the adjoining portions of the two side panels 12 and 14 are formed with a pair of fold sections 17. The fold sections 17 are defined by a pair of longitudinal fold lines 18 extending across the top panel 13, a pair of channel-shaped cut lines 19 disposed laterally in the adjacent portions of the side panels 12 and 14, and a cut line 20 extending longitudinally across the top panel from one lateral out line 19to the other. The pair of longitudinal fold lines 18 are spaced apart a distance appreciably greater than twice the height of the end wall of the erected carton and are positioned a short distance inboard from the opposite longitudinal edges of the rectangular carton blank. Each of the channel-shaped cut lines 19 connect proximate ends of the pair of longitudinal fold lines 18 and extend an appreciable distance into the adjoining side wall panels 12 or 14, as the case may be. The longitudinal out line 20 is disposed approximately intermediate the pair of longitudinal fold lines 18 and is so configured that it defines along the abutting edges of the two fold sections 17 a plurality of latching tongue portions 21 each of which have locking ear portions 22. The locking ears 22 of the latching tongue portions 21 are preferably wedgeor dovetail-shaped so that, when received in coextensive tongue-receiving openings formed in the bottom panel 15, the fold sections 17 will be firmly locked in position with respect to the bottom panel.

The bottom panel 15 of the carton blank is formed with coextensive openings 23 adapted and positioned to tongue-receiving openlngs 23 advantageously comprise a pair of laterally disposed cut lines 24 connected by a longitudinal cut line 25 and by a longitudinal fold line 26 spaced a short distance outboard of said cut line 25. The pair of lateral cut lines 24 are configured so that at their inner ends the cut lines are spaced apart a distance slightly greater than the extreme width of the locking cars 22 of the latching tongues 21, and at their outer ends the cut lines 24 are spaced apart a distance appreciably less than the extreme width of the locking ears 22 of the latching tongue portions (and preferably a distance the same as or only slightly greater than the minimum width of the dovetailshaped locking cars 22 adjacent the point where the latching tongue 21 joins the associated fold section 17). Thus, when the fold sections 17 are folded in an arcuate path downwardly and inwardly into the erected carton, the associated latching tongue portions 21 strike the bottom panel 15 between the cut lines 24 at the widest part of the corresponding tongue-receiving opening 23, thereby depressing the portion of the bottom panel disposed between the said cut lines 24 and allowing the locking ear portions 22 to enter and pass through the plane of the bottom panel and become lodged securely between the pair of lateral cut lines 24 at the narrowest part of said coextensive tongue-receiving opening.

In addition, the top and bottom panels of the carton blank are alsoadvantageously provided with channelshaped cut lines 27 the ends of which communicate with the proximate lateral fold lines 11, by means of which cut lines 27 ventilation openings will'be formed in the top and bottom panels of the carton when the carton blank is folded and erected. Moreover, in the embodiment of my invention shown in the drawing, the side wall panels 12 and 14 are provided with auxiliary portions 12a and 14a, respectively, which form foot members for the carton when the carton blank 10 is erected as herein described. In such case, an auxiliary longitudinal fold line 11a is provided in the side wall panel 14 to facilitate erection of the carton.

T o obtain a carton having sloping side walls despite the fact that the carton when-initially folded is formed with top and bottom walls of equal width, the portion of each fold section 17 adjacent the longitudinal fold line 18 connecting it to the top panel 13 is appreciably wider than the top panel, the portion of each fold section 17 adjacent the longitudinal cutline 20 is substantially the same width as the bottom panel 15 of the carton, and eachof the side wall panels 12 and 14 is formed with supplemental lateral fold lines 28 spaced an appreciable distance from the lateral fold line 11 defining the boundary between each side panel and the top panel 13. Advantageously, each of the foldsections 17 comprises a main end wall portion and two associated wing portions 29, in which Case the end'wall portion of the fold section 17 is wider than the top panel adjacent the longitudinal fold line 18 connecting it to the top panel and is approximately the same width as the bottom panel adjacent the longitudinal out line 20 defining the-bottom edge thereof. Moreover, as aconsequence of the diflerence in width betweenthe top and bottom-portions of the fold section 17, the wing portions 29are'connected to the associated main end wallportionof the fold section along an oblique fold line 30. The supplemental lateral fold lines 28' in each side wall panel extend from the proximate longitudinal edge of the carton blank to the proximate channelshaped cutline 19 where they connect with the proximate ends of the oblique fold lines 30 in the fold' sections 17. The fold lines.28.are all spaced the same distance from the proximate lateral. fold. line 11, a. distance approxi mately equal to one-half the difference in width between the top panel 12 and the, adjoining end wall portions of the fold sections 17. The thus-formed. fold sections 17 and supplemental fold lines.28 cooperate to provide the desired sloping side walls in a manner hereinafter more fully explained.

To erect the carton a transverse strip of glue 32 is applied tothe side panel 12 (or to the glue panel 16). When the side panels 12 and 14- of the carton are provided with auxiliary foot P01110118 12a and 14a, respectively, the glue strip 32 must be spaced an appropriate distance inboard of the outer lateral edge of the side panel 12, as shown in Fig. 1 of the drawing. In addition, in such case glue is also applied in a strip 33 along the auxiliary foot portions 14a of the side wall panel 14 as shown in Fig. 1, care being taken to avoid applying glue to any part of the bottom panel 15, and in particular to any of the cutout portions thereof that might as a result interfere with the ready erection of the carton. The carton blank is then folded about the lateral fold line 11 defining the boundary between the side wall panel 14 and the bottom panel 15 (or, if the blank 10 is provided with the auxiliary foot portions 12a and 14a as described, the blank is first folded about the auxiliary lateral fold line 1111) so that the bottom panel directly overlies the adjoining side wall panel 14. The side wall panel 12 is then folded about the proximate lateral 'fold line 11 so that the panel 12 directly overlies the top panel 13 (and the fold sections 17) and the glue strip 32 adheres to the glue panel 16 of the carton.

Because the two side wall panels and the top and bottom wall panels are of the same width, respectively, the foregoing gluing and folding operations are best carried out by high speed automatic machinery. Moreover, the resulting folded and glued carton is a flat structure that can be packed and shipped in the flattened condition to consumers who complete the erection of the carton and fill it with the desired commodity. The final erection of the carton is carried out by folding the blank about all of the lateral fold lines 11 until the two side walls are parallel to each other and are substantially normal to the top and bottom walls. At this stage in the erection of the carton, the top wall 13 is' still the same width as the bottom wall 15 of the carton, the general appearance of the carton being as shown at the left-hand end of Fig. 2 of the drawing. It is to be noted that at this juncture the side walls and top wall are hinged about the lateral fold lines 11 defining the boundary between the top wall and the two side walls.

The fold sections 17 of the top panel are then folded downwardly and inwardly into the interior of the carton to form the end walls thereof. Due to the fact that the portion of the fold section 17 adjoining the top panel 13 is Wider than the top panel, the fold section 17 cannot be folded downwardly into the carton unless a small portion of each of the two side wall panels is added to the top panel to increase the 'width of the top panel. Accordingly, as the fold section 17 is folded downwardly into the carton, the two side wall panels are automatically folded about the supplemental fold lines 28 as shown at the right-hand end of Fig. 2, whereby the portions of the two side panels between these supplemental fold lines 28 and the proximate fold lines 11 become added to the top panel 13. This addition of a portion of the two side wall panels to the top panel occurs automatically when the fold sections 17 are folded as described. With the width of the top panel increased by the addition of a portion of the adjoining side wall panels, the top wall of the carton is now wider than the bottom 'wall and, as a consequence, the side walls of the carton slope outwardly toward the top wall, as shown at the right-hand end of Fig. 2.

As each fold section 17 is pressed into the interior of the carton, the wing portions 29 thereof are automatically folded inwardly and upwardly until they are at right angles to the end wall portion of the fold sections 17. Moreover, as each fold section 17 is moved downwardly in its arcuate path of travel, the latching tongue portions 21 thereof strike the bottom panel 15 at the corresponding tongue-receiving openings 23, thereby depressing the flap portions 35 of bottom panel disposed between the pairs of lateral cut lines 24. The locking ears 22 thereupon enter and pass through the plane of the bottom panel and, as the fold section 17 approaches its final position, become firmly wedged between the pairs of cut lines 24 at their narrow outboard ends. As the fold section 17 approaches its final position, the latching tongue portions 21 slide off the outboard edges (defined by the out line 25) of the aforesaid depressed flap portions 35, thereby allowing these flap portions to spring back to the plane of the bottom panel. Simultaneously, the small hinged portions 36 of the bottom panel between the longitudinal out line 25 and the fold line 26 are folded downwardly as shown in Fig. 3 to provide a permanent opening in the bottom panel just large enough to accommodate the latching tongues 21 at their narrowest point. The fold sections 17 are thus firmly locked in their final position, inward and outward movement being prevented by the abutting edges of the flap portion 35 and the hinged portion 36 of the bottom panel which bear against the latching tongues 21, and vertical separation being prevented by the dovetail-shaped ears 22 which are wedged firmly in the narrowest part of the tongue-receiving opening 23. The construction and cooperation of the latching tongue and locking ear portions of the fold section 17 and the coextensive latching tongue portionreceiving openings 23 in the bottom panel are shown clearly in Fig. 3 of the drawing.

A modification of my novel carton construction is shown in Figs. 4 and 5 of the drawing the purpose of which is to provide a five-sided or open top carton of greater length than heretofore possible. In the carton construction of the type hereinbefore described the length of the erected carton (which corresponds to the lateral dimension of the carton blank) is a function of and is limited by the height of the side walls of the carton. That is to say, if a carton has side walls of a given height, the end walls of the carton must of necessity be approximately the same height, and therefore the parallel fold lines 18 by which the end walls (i.e., the fold sections 17 are hinged to the top panel must be spaced apart a distance only slightly greater than twice the height of the side walls of the carton. Thus, the length of the carton, which is approximately equal to the distance separating the pair of fold lines 18, is ordinarily only slightly greater than twice the height of the end walls and side walls of the erected carton.

By means of the modification of the carton blank 10 shown in Figs. 4 and 5 of the drawing, it is possible to space the pair of longitudinal fold lines 18 a distance apart greater than heretofore possible, thereby increasing the length of the erected carton by a corresponding amount. To provide for the increase in lateral spacing of the longitudinal fold lines 18, the overall length of each fold section 17 must be increased by a corresponding amount. As a result, the overall length of each fold section is greater than the desired height of the end Wall of the erected carton, and therefore the fold sections must be modified to make allowance for their excess length. Accordingly, as shown best in Fig. 4, the fold sections 17 are separated at their abutting edges by a longitudinal out line 40 spaced approximately intermediate the longitudinal fold lines 18. Each fold section 17 is further formed with a fold line- 41 extending longitudinally across the fold section and spaced a distance inboard from the proximate longitudinal fold line 18 a distance approximately equal to the height of the end wall of the erected carton. The fold sections 17 are further formed with dovetail-shaped cut lines 42 the ends of which communicate with the fold line 41, the said dovetail cut lines 42 defining the latching tongue portion 21 and locking ear portions 22 of the end wall of the carton.

To facilitate folding the modified fold sections 17 downwardly into the carton, the bottom edges of the wing portions 19 are defined by oblique cut lines 44 which extend from the ends of the fold lines 41 to the proximate lateral out line 19. Moreover, the portions of the blank bounded by the cut lines 19, 44 and 45 are discarded to prevent undue interference with the erection of the carton.

When the fold sections 17 modified as described are folded downwardly and inwardly into the interior of the partly erected carton, the bottom edge of the excess portion 43 of the fold section strikes the bottom wall of the carton and folds about the fold line 41 as shown in Fig. 5. With the excess portion 43 of the end wall fold section 17 thus folded out of the way, the latching tongue portions 21 enter the bottom wall through the coextensive tongue-receiving openings 23 therein in the manner de scribed hereinbefore.

In a further modification of my invention the carton blank 10 is adapted to form a carton the end walls of which slope or diverge outwardly toward the top of the carton, in addition to the sloping side Walls hereinbefore described. In this modification of the carton blank the distance between the longitudinal cut line 29 (or the longitudinal fold lines 41) and the proximate fold line 13 is appreciably greater than the interior height of the erected carton, resulting in fold sections 17 the end Wall portions of which are appreciably longer than the height of the carton interior. When the overlong fold sections 17 are folded downwardly and inwardly into the erected carton, the lower edges of the fold sections (de fined by said out line 20 or said fold lines 41) strike the bottom panel of the carton before the fold sections become normal to the bottom panel. Thus, when the fold sections 17 come to rest with the latching tongue portions 21 thereof received in the coextensive opening 23 of the bottom panel, the resulting end walls are at a slightly obtuse angle with respect to the bottom wall; the lower edges of the end walls being slightly closer together than the upper edges thereof. The sloping side walls and end walls of the carton help support the contents contained in the upper part of the carton and hence help avoid undue pressure on any perishable and easily damaged articles contained in the lower part of the carton.

It will be seen from the foregoing description that the carton blank of my invention possesses all of the advantages inherent in a blank that can be folded, glued and erected by high speed machinery, and at the same time possesses all the advantages of a carton having sloping side walls which contribute to the utility and versatility of the carton structure. Among the latter advantages are the ability of the cartons to be stacked one on top of the other as shown in Fig. 6, the support the sloping side walls provide for the contents of the carton, and the ease with which the stacked cartons can be treated with a gaseous agent or ventilated, as the case may be.

I claim:

1. A carton blank comprising a substantially rectangular piece of sheet material provided with a plurality of spaced parallel fold lines extending laterally across the blank, said lateral fold lines defining serially a first side panel, a top panel, a second side panel, a bottom panel, and a glue panel, the lateral fold lines defining the top panel being spaced apart the same distance as the lateral fold lines defining the bottom panel, the top panel and the adjoining portion of the two side panels being formed with a pair of fold sections each connected at its top edge to the top panel along one of a pair of Iongitudinal fold lines and each adapted to be folded downwardly and inwardly into the interior of the erected carton to form one of the end walls thereof, each fold section being wider than the top panel adjacent the top edge of said fold section and being the same width as the bottom panel adjacent the bottom edge of said fold section, each side panel additionally being provided with supplemental lateral fold lines spaced an appreciable distance from the lateral fold line defining the boundary between said side panel and the top panel, each of said supplemental lateral fold lines extending from the longitudinal edge of the rectangular carton blank to the proximate edge of said fold sections, the bottom edges of said fold sections being configured to define latching tongue portions the sides of which are provided with locking ear portions, said bottom panel being provided with openings adapted to receive and retain the latching tongue portions of each fold section when the fold section is folded downwardly and inwardly into the interior of the erected carton.

2. A carton blank comprising a substantially rectangular piece of sheet material provided with a plurality of spaced parallel fold lines extending laterally across the blank, said lateral fold lines defining serially a first side panel, a top panel, a second side panel, a bottom panel, and a glue panel, the lateral fold lines defining the top panel being spaced apart the same distance as the lateral fold lines defining the bottom panel, the top panel and the adjoining poi-tion of the two side panels being formed with a pair of fold sections adapted to be folded downwardly and inwardly into the interior of the erected carton to form the end walls thereof, each of said fold sections being connected to the top panel along one of a pair of longitudinal fold lines extending across the top panel adjacent each longitudinal edge thereof and being separated from the other fold section by a longitudinal cut line extending across the top panel approximately intermediate of said longitudinal fold lines, said longitudinal cut line defining the bottom edge of both of said fold sections and being configured to define latching tongue portions the sides of which are formed with locking ear portions, each fold section being wider than the top panel adjacent the longitudinal fold line connecting said fold section to the top panel and being the same width as the bottom panel adjacent the longitudinal cut line defining the bottom edge thereof, each side panel additionally being provided with supplemental lateral fold lines spaced an appreciable distance from the lateral fold line defining the boundary between each side panel and the top panel, each supplemental lateral fold line extending from the longitudinal edge of the rectangular carton blank to the proximate edge of said fold sections, said bottom panel being provided with openings adapted to receive the latching tongue portions of each fold section when the fold section is folded downwardly and inwardly into the interior of the erected carton, each of said openings in the bottom panel comprising two laterally disposed cut lines and a longitudinally disposed cut line extending between said laterally disposed cut lines.

3. A carton blank comprising a substantially rectangular piece of sheet material provided with a plurality of spaced parallel fold lines extending laterally across the blank, said lateral fold lines defining serially a first side panel, a top panel, a second side panel, a bottom panel, and a glue panel, the lateral fold lines defining the top panel being spaced apart the same distance as the lateral fold lines defining the bottom panel, the top panel and the adjoining portion of each side panel being formed with a pair of fold sections adapted to be folded downwardly and inwardly into the interior of the erected carton to form the end walls thereof, said pair of fold sections being defined by (a) a pair of longitudinal fold lines extending across the top panel adjacent each longitudinal edge thereof, (b) a pair of laterally disposed channel-shaped cut lines each connecting the proximate ends of said pair of longitudinal fold lines and each extending an appreciable distance into the proximate side wall panel, and (c) a longitudinal out line connecting the two channel-shaped cut lines approximately intermediate said pair of longitudinal fold lines, said longitudinal cut line defining the bottom edge of both of said fold sections, each fold section being wider than the top panel adjacent the longitudinal fold line connecting said fold section to the top panel and being the same width as the bottom panel adjacent the longitudinal cut line defining the bottom edge thereof, each side panel additionally being provided with supplemental lateral fold lines spaced an appreciable distance from the lateral fold line defining the boundary between said side panel and the top panel, each supplemental lateral fold line extending from the proximate longitudinal edge of the rectangular carton blank to the proximate channelshaped cut line of said fold sections, the bottom edges of said fold sections being formed with latching tongue portions the sides of which are formed with locking ear portions, said bottom panel being provided with openings adapted to receive the latching tongue portions of each fold section when the fold section is folded down wardly and inwardly into the interior of the erected oarton, each of said openings in the bottom panel being formed from two laterally disposed cut lines and a longitudinally disposed cut line extending between said laterally disposed cut lines.

4. A carton blank comprising a substantially rectangular piece of sheet material provided with a plurality of spaced parallel fold lines extending laterally across the blank, said lateral fold lines defining serially a first side panel, a top panel, a second side panel, a bottom panel, and a glue panel, the lateral fold lines defining the top panel being spaced apart the same distance as the lateral fold lines defining the bottom panel, the top panel and the adjoining portion of each side panel being formed with a pair of fold sections adapted to be folded downwardly and inwardly into the interior of the erected carton to form the end walls thereof, said pair of fold sections being defined by (a) a pair of longitudinal fold lines extending across the top panel adjacent the longitudinal edges thereof and being spaced apart a distance appreciably greater than twice the height of the end wall of the erected carton, (b) a pair of laterally disposed channel-shaped out lines each connecting the proximate ends of the pair of longitudinal fold lines and each extending an appreciable distance into the proximate side wall panel and (c) at least one longitudinal cut line connecting the two channel-shaped cut lines approximately intermediate of said longitudinal fold lines and defining the bottom edges of said fold sections, each of said fold sections being connected to said top panel along one of said pair of longitudinal fold lines and comprising an end wall portion and two wing portions, the end wall portions of each fold section being wider than the top panel adjacent the longitudinal fold line connecting said fold section to the top panel and being the same width as the bottom panel adjacent the longitudinal out line defining the bottom edge thereof each of said wing portions being connected to the associated end wall portion along an oblique fold line, each side panel additionally being formed with supplemental lateral fold lines in each side panel spaced an appreciable distance from the lateral fold line defining the boundary between each side panel and the top panel, each supplemental lateral fold lines extending from the longitudinal edge of the rectangular carton blank to the proximate channel-shaped cut line of said fold sections and connecting to the outboard end of the proximate oblique fold line, the longitudinal out line defining the bottom edges of said fold sections being configured to define lactbing tongue portions the sides of which are formed with locking ear portions, said bottom panel being provided with openings adapted to receive corresponding latching tongue portions of each fold section when the fold section is folded downwardly and inwardly into the interior of the erected carton, each of said openings in the bottom panel comprising two laterally disposed cut lines and a longitudinal out line extending between said laterally disposed cut lines.

5. A carton blank according to claim 4 in which the pair of fold sections are defined by (a) a first pair of longitudinal fold lines extending across the top panel adjacent the longitudinal edges thereof, (b) a pair of laterally disposed channel-shaped cut lines each connecting the proximate ends of the pair of longitudinal fold lines and each extending an appreciable distance into the proximate side Wall panel, (c) a longitudinal out line connecting the two channel-shaped cut lines approximately intermediate said first pair of longitudinal fold lines, and (d) a second pair of longitudinal fold lines disposed one on either side of said longitudinal out line and each spaced from the proximate longitudinal fold line of said first pair of fold lines a distance approximately equal to the interior height of the erected carton, each of said fold sections being formed with at least one dovetailshaped cut line the converging ends of which connect with the proximate longitudinal fold line of said second pair of fold lines, said dovetail-shaped cut lines defining latching tongue portions adapted to be received in the corresponding openings formed in the bottom panel of the erected carton.

6. A carton blank according to claim 4 in which the locking ears of the latching tongue portions are dovetailshaped, and in which the corresponding tongue-receiving opening in the bottom panel is defined by a pair of laterally disposed cut lines, a longitudinal cut line and a longitudinal fold line, both of said longitudinal lines extending between said laterally disposed cut lines, the inboard ends of said pair of laterally disposed cut lines being spaced apart a distance greater than the extreme width of the locking ears of the corresponding latching tongue portion and the outboard ends of said pair of laterally disposed cut lines being spaced apart a distance approximately the same as the minimum width of said dovetail-shaped locking ears, said longitudinal fold line connecting the said outboard ends of said laterally disposed cut lines, and said longitudinal out line being spaced a short distance inboard of said longitudinal fold line.

7. A collapsible open top carton formed from a rectangular carton blank initially provided with two side wall panels of equal width, a top wall panel and a bottom wall panel of equal width, the integral connection of the four panels being completed by the gluing together of the portions of the panels at the extremities of the blank and a pair of fold sections formed from the center portion of the top wall panel and adjoining portions of the two side wall panels, said carton comprising a bottom wall formed from said bottom wall panel, two side walls formed from the lower portions of said side wall panels, a partial top wall formed from the outboard portions of the top wall panel and adjacent upper portions of the side wall panels, and two end walls formed from said pair of fold sections, said fold sections from which said end walls are formed being wider than the top wall panel adjacent the upper ed-ges thereof and being the same width as the bottom wall panel adjacent the lower edges thereof, the said upper portions of each side wall panel adjacent the said outboard portions of said top wall panel being disposed substantially in the plane of the top wall of the erected carton whereby the top wall of the carton is wider than the bottom wall of the carton and the side walls of the carton diverge outwardly from the bottom wall toward the top wall thereof.

References Cited in the file of this patent UNITED STATES PATENTS 2,076,844 Homes Apr. 13, 1937 2,637,482 Broderick May 5, 1953 2,640,589 Foster et al. June 2, 1953 FOREIGN PATENTS 608,406 Great Britain Sept. 15, 1948 

